Research in safety of processed food has focused on the use of anti-microbial compounds to suppress pathogenic bacteria growth
suchas Listeria monocytogenes and Staphylococcus aureus. Previous studies developed an anti-microbial edible film, incorporating
the bacteriocin nisin. Nisin effectiveness was based on both nisin desorption from the film and its diffusion in the food product. In
this present work, and as a preliminary study, nisin diffusion in agarose gel was investigated. The apparent diffusion coefficients were
calculated, taking into account factors influencing the diffusion rates such as nisin concentration, diffusion time and temperature.
Influence of agarose content on nisin diffusion was also evaluated. As a result, Fick’s second law well represented nisin diffusion in
agarose gel. In 3% (w/w) gel, the diffusion coefficient values varied between 1.92 · 1011 and 8.14 · 1011 m2 s1 for temperatures
ranged between 5.4 and 22.3 C. Diffusion phenomena satisfied Arrhenius relationship. Agarose content from 3% to 6% did not have
any effect on nisin diffusion. However, agarose content of 8% significantly reduced nisin diffusion in agarose gel cylinders.
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